#include<iostream>
#include<iomanip>
#include<cmath>
#define PI 3.14
double calV(int h, int r);
using namespace std;
int main()
{
    int h, r;
    cin >> h >> r;
    double v = calV(h, r);
    cout << ceil(20.0 / v) << endl;
    return 0;
}
double calV(int h, int r)
{
    return ((float)h * PI * (float)r * r) / 1000.0;
}